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Comment by Dr. Krishna Kumari Challa 7 hours ago

Frozen RNA survived 50,000 years
Researchers have found the oldest RNA molecules to date in mummified woolly mammoth tissue. RNA is a fragile molecule, which makes intact ancient samples few and far between. But such samples are sought after because analysing ancient RNA could shed light on the gene activity of extinct animals. Scientists used enzymes to convert RNA in the mammoth tissue to DNA, and then reverse-engineered the original RNA sequences. This technique recovered fragments of RNA from three samples, dated to between 39,000 and 52,000 years old.

https://www.cell.com/cell/fulltext/S0092-8674(25)01231-0?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0092867425012310%3Fshowall%3Dtrue

https://www.science.org/content/article/forty-thousand-year-old-mam...

Comment by Dr. Krishna Kumari Challa 7 hours ago

Learning to see after being born blind: Brain imaging study highlights infant adaptability

Some babies are born with early blindness due to dense bilateral congenital cataracts, requiring surgery to restore their sight. This period of several months without vision can leave a lasting mark on how the brain processes visual details, but surprisingly little on the recognition of faces, objects, or words. This is the main finding of an international study conducted by neuroscientist.

Using brain imaging, the researchers compared adults who had undergone surgery for congenital cataracts as babies with people born with normal vision. The results are striking: in people born with cataracts, the area of the brain that analyzes small visual details (contours, contrasts, etc.) retains a lasting alteration from this early blindness.

On the other hand, the more advanced regions of the visual brain, responsible for recognizing faces, objects, and words, function almost normally. These "biological" results have been validated by computer models involving artificial neural networks. This distinction between altered and preserved areas of the brain paves the way for new treatments. In the future, clinicians may be able to offer visual therapies that are better tailored to each patient.

Babies' brains are highly adaptable . Even if vision is lacking at the very beginning of life, the brain can adapt and learn to recognize the world around it even on the basis of degraded information.

These findings also challenge the idea of a single "critical period" for visual development. Some areas of the brain are more vulnerable to early vision loss, while others retain a surprising capacity for recovery. The brain is both fragile and resilient. Early experiences matter, but they don't determine everything.

Impact of a transient neonatal visual deprivation on the development of the ventral occipito-temporal cortex in humans, Nature Communications (2025).

https://www.nature.com/articles/s41467-025-65468-7#:~:text=We%20sho...

Comment by Dr. Krishna Kumari Challa 7 hours ago

New study identifies part of brain animals use to make inferences

Animals survive in changing and unpredictable environments by not merely responding to new circumstances, but also, like humans, by forming inferences about their surroundings—for instance, squirrels understand that certain bird noises don't signal the presence of a predator, so they won't seek shelter when they later hear these same sounds. But less clear is how the brain works to create these inferences.

In a study published in the journal Neuron, a team of  researchers identified a particular part of the brain that serves as an "inference engine." The region, the orbitofrontal  cortex (OFC), allows animals to update their understanding of their surroundings based on changing circumstances.

To survive, animals cannot simply react to their surroundings. They must generalize and make inferences—a cognitive process that is among the most vital and complicated operations that nervous systems perform. These findings advance our knowledge of how the brain works in applying what we've learned.

The scientists add that the results offer promise for better understanding the nature of neuropsychiatric disorders, such as bipolar disorder and schizophrenia, in which our ability to make inferences is diminished.

In the experiments conducted when the brain's OFC was disrupted, the trained rats could no longer update their understanding of what the other available rewards might be—specifically, they couldn't make distinctions among hidden states.

These results, based on recordings of more than 10,000 neurons, suggest that the OFC is directly involved in helping the brain make inferences in changing situations.

 The orbitofrontal cortex updates beliefs for state inference, Neuron (2025). DOI: 10.1016/j.neuron.2025.10.024. www.cell.com/neuron/fulltext/S0896-6273(25)00805-0

Comment by Dr. Krishna Kumari Challa 7 hours ago

Dogs 10,000 years ago roamed with bands of humans and came in all shapes and sizes
Analysis of ancient dog skulls and genomes indicates that significant physical and genetic diversity in dogs emerged over 10,000 years ago, predating modern selective breeding. Distinctive dog-like skulls appeared around 11,000 years ago, and ancient DNA reveals that dogs often migrated with human groups, reflecting complex, intertwined histories and early biocultural exchanges.

https://theconversation.com/dogs-10-000-years-ago-roamed-with-bands...

Comment by Dr. Krishna Kumari Challa 8 hours ago

Nearly half (47%) of all sea turtles; a third (35%) of seabirds; and 12% of marine mammals in the dataset had plastics in their digestive tracts at their time of death. Overall, one in five (21.5%) of the animals recorded had ingested plastics, often of varying types. Additional findings included:
Seabirds
Of seabirds that ate plastic, 92% ate hard plastics, 9% ate soft plastics, 8% ate fishing debris, 6% ate rubber, and 5% ate foams, with many individuals eating multiple plastic types.
Seabirds are especially vulnerable to synthetic rubber: just six pieces, each smaller than a pea, are 90% likely to cause death.
Sea turtles
Of sea turtles that ate plastic, 69% ate soft plastics, 58% ate fishing debris, 42% ate hard plastics, 7% ate foam, 4% ate synthetic rubbers, and 1% ate synthetic cloth.
Sea turtles, which on average weigh several hundred pounds, are especially vulnerable to soft plastics, like plastic bags: just 342 pieces, each about the size of a pea, would be lethal with 90% certainty.
Mammals
Of marine mammals that ate plastic, 72% ate fishing debris, 10% ate soft plastics, 5% ate rubber, 3% ate hard plastics, 2% ate foam, and 0.7% ate synthetic cloth.
Marine mammals are especially vulnerable to fishing debris: 28 pieces, each smaller than a tennis ball, are enough to kill a sperm whale in 90% of cases.
Threatened species and broader impacts
The study also found that nearly half of the individual animals who had ingested plastics are red-listed as threatened—that is, near-threatened, vulnerable, endangered or critically endangered—by the IUCN. Notably, the study only analyzed the impacts of ingesting large plastics (greater than 5 millimeters) on these species, and did not account for all plastic impacts and interactions. For example, they excluded entanglement, sublethal impacts of ingestion that can impact overall animal health, and microplastics consumed.

This research really drives home how ocean plastics are an existential threat to the diversity of life on our planet.

 Murphy, Erin L., A quantitative risk assessment framework for mortality due to macroplastic ingestion in seabirds, marine mammals, and sea turtles, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2415492122. doi.org/10.1073/pnas.2415492122

Part2

Comment by Dr. Krishna Kumari Challa 8 hours ago

Lethal dose of plastics for ocean wildlife: Surprisingly small amounts can kill seabirds, sea turtles and marine mammals

By studying more than 10,000 necropsies, researchers now know how much plastic it takes to kill seabirds, sea turtles, and marine mammals, and the lethal dose is much smaller than you might think. Their new study titled "A quantitative risk assessment framework for mortality due to macroplastic ingestion in seabirds, marine mammals, and sea turtles" is published in the Proceedings of the National Academy of Sciences.

Led by Ocean Conservancy researchers, the paper is the most comprehensive study yet to quantify the extent to which a range of plastic types—from soft, flexible plastics like bags and food wrappers; to balloon pieces; to hard plastics ranging from fragments to whole items like beverage bottles—result in the death of seabirds, sea turtles, and marine mammals that consume them.

The study reveals that, on average, consuming less than three sugar cubes' worth of plastics for seabirds like Atlantic puffins (which measure approximately 28 centimeters, or 11 inches, in length); just over two baseballs' worth of plastics for sea turtles like Loggerheads (90 centimeters or 35 inches); and about a soccer ball's worth of plastics for marine mammals like harbor porpoises (1.5 meters, or 60 inches), has a 90% likelihood of death.

At the 50% mortality threshold, the volumes are even more startling: consuming less than one sugar cube's worth of plastics kills one in two Atlantic puffins; less than half a baseball's worth of plastics kills one in two Loggerhead turtles; and less than a sixth of a soccer ball kills one in two harbor porpoises.

The lethal dose varies based on the species, the animal's size, the type of plastic it's consuming, and other factors, but overall it's much smaller than you might think, which is troubling when you consider that more than a garbage truck's worth of plastics enters the ocean every minute.

Part 1

Comment by Dr. Krishna Kumari Challa 8 hours ago

Reducing arsenic in drinking water cuts risk of death, even after years of chronic exposure: 20-year study

Arsenic is among the most common chemical pollutants of ground water.

Arsenic is a naturally occurring element that accumulates in groundwater, and because it has no taste or odor, people can unknowingly drink contaminated water for years.

A 20-year study of nearly 11,000 adults in Bangladesh found that lowering arsenic levels in drinking water was associated with up to a 50% lower risk of death from heart disease, cancer and other chronic illnesses, compared with continued exposure.

The study provides the first long-term, individual-level evidence that reducing arsenic exposure may lower mortality, even among people exposed to the toxic contaminant for years.

The landmark analysis by researchers is important for public health because groundwater contamination from naturally occurring arsenic remains a serious issue worldwide.

The study shows what happens when people who are chronically exposed to arsenic are no longer exposed. You're not just preventing deaths from future exposure, but also from past exposure.

The results provide the clearest evidence to date of the link between arsenic reduction and lower mortality.

For two decades, the research team followed each participant's health and repeatedly collected urine samples to track exposure, which they say strengthened the accuracy of their findings.

People whose urinary arsenic levels dropped from high to low had mortality rates identical to those who had consistently low exposure throughout the duration of the study. The larger the drop in arsenic levels, the greater the decrease in mortality risk. By contrast, individuals who continued drinking high-arsenic water saw no reduction in their risk of death from chronic disease.

 Arsenic Exposure Reduction and Chronic Disease Mortality, JAMA (2025). jamanetwork.com/journals/jama/ … 1001/jama.2025.19161

Comment by Dr. Krishna Kumari Challa 8 hours ago

Ferroelectric materials, first discovered in 1920, have a natural electrical polarization that can be reversed by an electric field. That polarization remains reversed even once the electric field has been removed.

The materials are dielectric, meaning they can be polarized by the application of an electric field. That makes them highly effective in capacitors.

Ferroelectrics are also piezoelectric, which means they can generate electric properties in response to mechanical energy, and vice versa. This quality can be used in sonars, fire sensors, tiny speakers in a cell phone or actuators that precisely form letters in an inkjet printer.

All these properties can be enhanced by manipulating the phase boundary of ferroelectric materials.
In a lead-based ferroelectric, such as lead zirconate titanate, one can chemically tune the compositions to land right at the phase.
Lead-free ferroelectrics, however, contain highly volatile alkaline metals, which can become a gas and evaporate when chemically tuned.
The researchers instead created a thin film of the lead-free ferroelectric material sodium niobate (NaNbO3). The material is known to have a complex crystalline ground state structure at room temperature. It is also flexible. Scientists have long known that changing the temperature of sodium niobate can produce multiple phases, or different arrangements of atoms.
Instead of a chemical process or manipulating the temperature, the researchers changed the structure of the atoms in sodium niobate by strain.

They grew a thin film of sodium niobate on a substrate. The structure of the atoms in the sodium niobate contract and expand as they try to match the structure of the atoms in the substrate. The process creates strain on the sodium niobate.

"What is quite remarkable with sodium niobate is if you change the length a little bit, the phases change a lot.
To the researchers' surprise, the strain caused the sodium niobate to have three different phases at once, which optimizes the useful ferroelectric properties of the material by creating more boundaries.
The experiments were conducted at room temperature. The next step will be seeing if sodium niobate responds to strain in the same way at extreme temperatures ranging from minus 270 C to 1,000 C above.

Reza Ghanbari et al, Strain-induced lead-free morphotropic phase boundary, Nature Communications (2025). DOI: 10.1038/s41467-025-63041-w

Part 2

Comment by Dr. Krishna Kumari Challa 8 hours ago

Lead-free alternative discovered for essential electronics component

Ferroelectric materials are used in infrared cameras, medical ultrasounds, computer memory and actuators that turn electric properties into mechanical properties and vice-versa. Most of these essential materials, however, contain lead and can therefore be toxic.

Therefore, for the last 10 years, there has been a huge initiative all over the world to find ferroelectric materials that do not contain lead.

The atoms in a ferroelectric material can have more than one crystalline structure. Where two crystalline structures meet is called a phase boundary, and the properties that make ferroelectric materials useful are strongest at these boundaries.

Using chemical processes, scientists have manipulated the phase boundaries of lead-based ferroelectric materials to create higher performance and smaller devices. Chemically tuning the phase boundaries of lead-free ferroelectric material, however, has been challenging.

New research found a way to enhance lead-free ferroelectrics using strain, or mechanical force, rather than a chemical process. The discovery could produce lead-free ferroelectric components, opening new possibilities for devices and sensors that could be implanted in humans.

Part 1

Comment by Dr. Krishna Kumari Challa 9 hours ago

Parasitic ant tricks workers into killing their queen, then takes the throne

Scientists document a new form of host manipulation where an invading, parasitic ant queen "tricks" ant workers into killing their queen mother. The invading ant integrates herself into the nest by pretending to be a member of the colony, then sprays the host queen with fluid that causes her daughters to turn against her. The parasitic queen then usurps the throne, having the workers serve her instead as the new queen regent. This work was published in Current Biology on November 17.

Matricide, a behavior where offspring kill or eat their mother, is a rarely seen phenomenon in nature. Despite appearing maladaptive at first glance, it does offer advantages by either nourishing the young and giving the mother indirect benefits through increased offspring survival or allowing the young to invest in offspring of their own.

Up until now, only two types of matricide have been recorded in which either the mother or offspring benefit. In this novel matricide that researchers reported, neither profit; only the parasitic third party.

The ants Lasius orientalis and umbratus, commonly referred to as the "bad-smell ants" in Japanese, are so-called "social parasites" that execute a covert operation to infiltrate and eventually take over the colony of their unsuspecting ant queen hosts, Lasius flavus and japonicus, respectively. The parasitic queen takes advantage of ants' reliance on smell to identify both friends and foes to dupe unsuspecting worker ants into believing she is part of the family.

Ants live in the world of odors. 

Before infiltrating the nest, the parasitic queen stealthily acquires the colony's odor on her body from workers walking outside so that she is not recognized as the enemy.

Once these "bad-smell" ants have been accepted by the colony's workers and locate the queen, the parasitic ant douses her with a foul-smelling chemical researchers presume to be formic acid—a chemical unique to some ants and stored in a specialized organ.

The parasitic ants exploit that ability to recognize odors by spraying formic acid to disguise the queen's normal scent with a repugnant one. This causes the daughters, who normally protected their queen mother, to attack her as an enemy.

Then, like fleeing the scene of the crime, the parasitic queen immediately (but temporarily) retreats. "She knows the odor of formic acid is very dangerous, because if host workers perceive the odor they would immediately attack her as well.

She will periodically return and spray the queen multiple times until the workers have killed and disposed of their mother queen. Then, once the dust has settled, the parasitic ant queen returns and begins laying eggs of her own. With this newly accepted parasitic queen in the colony and no other queen to compete with, the matricidal workers begin taking care of her and her offspring instead.

 Host daughter ants manipulated into unwitting matricide by a social parasitic queen, Current Biology (2025). DOI: 10.1016/j.cub.2025.09.037. www.cell.com/current-biology/f … 0960-9822(25)01207-2

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